3mm in 3/16 brake line: suggestions??

[jebster]

I need to mount some 3mm bolts (or set screws) in some brake lines. Has to be pretty sturdy and has to be 3mm. Since I can't just thread thread in the bolt (like I would with a 4mm) I need a different way. Things I have considered are:

1. Braze in a long set screw of bolt (cut the head off) and use a nut. I'm worried I won't get the screw soldered in solid enough given the small space between the screw and tubing wall may not allow for enough solder flow.
2. JB weld in a set screw or bolt. I haven't used this before so I'm not sure about the strength.
3. ???

I'm doing this to hook revo rodends to a snowplow mount so it needs to be able to handle some serious shocks, like when I slam the blade into a crack in my driveway!

[Johnnysplits]

JB weld is super strong!!

[jebster]

Originally Posted by Johnnysplits

JB weld is super strong!!

Will it get enough of a bond with the inside of the tube? Would I need to rough it up somehow? Maybe run a 4mm tap in to give it some ridges?

[6sharky9]

why not a steel tube you can thread into?...If you already have a tap and the all thread or bolts to cut for it just get a tube...Can get one for probably the cost of a tube of JB weld and it be much much stronger.

[jebster]

Originally Posted by 6sharky9

why not a steel tube you can thread into?...If you already have a tap and the all thread or bolts to cut for it just get a tube...Can get one for probably the cost of a tube of JB weld and it be much much stronger.

Not a bad idea but too late for that. I already have the frame made up with brake tubing. Not something I want to start over on. Good idea for the next project.

[Johnnysplits]

Originally Posted by jebster

Will it get enough of a bond with the inside of the tube? Would I need to rough it up somehow? Maybe run a 4mm tap in to give it some ridges?

Good idea! But that stuff sticks pretty well without help. I learned this the hard way, when I did something very stupid with the stuff.

[C*H*U*D]

I've silver soldered M3 nuts to the ends of tubes before. Thread the nut onto an M3 bolt, and slide the bolt into the tube. The bolt holds the nut in place, and keeps it square to the end of the tube. If you are careful, you should not have a problem with the bolt being soldered into place.

[gr33nlemon]

If you're using revo ends isn't a 3mm too small? If 3mm is what you want what about using a flanged 3mm nut?

[jebster]

Originally Posted by gr33nlemon

If you're using revo ends isn't a 3mm too small? If 3mm is what you want what about using a flanged 3mm nut?

The ball uses a 3mm, which is what I needed to mount to the brake line. In the end I decided to give the JB weld a try. Worst case it doesn't work and I try something else.

[gr33nlemon]

Oh I was thinking for the shank. My bad.

[motsco]

for 3/16 brake line I use 6 32 screws and a 6 32 tap, fits pretty good.

[bob1961]

I have threaded 4mm in 3/16" brake line....